Just a quick back-of-the-envelope calculation shows that so much overtime equates to about 60 hours a week in overtime alone; 52 weeks a year.

So when state records last month showed the top overtime earner in New York state government received 3,312 hours of overtime last year, the first question from dozens of readers to the USA Today Network's Albany Bureau was: How could it be?

Turns out, it can be.

Debborah Casais, an information technician in the Office of Information Technology Services, raked up so much overtime because of a confluence of circumstances, state officials said.

The state last year was switching from its own 24/7 computer help desk to a private call center run by IBM in Buffalo.

How it happened

So there was a lot of extra work, state officials said, particularly when a department is running all day and night.

There was also another important factor: Union workers can collect overtime after they hit 40 hours of work in a week.

And union contracts allow for a worker to use vacation time on one day, then work a later shift in the same day to get the overtime, state officials said.

For example, a worker can take a vacation day from 9 a.m. to 5 p.m., but then work a night shift and get overtime when they hit the 40-hour mark for the week.

So while the hours for that day might suggest a 16-hour workday, the worker would have only been in the office for eight hours, state officials explained.

For a worker like Casais, who has since retired but was a veteran employee, they can have at least five weeks of vacation time to use each year, which can offset the actual hours in the office.

Overtime explained

That is part of what happened in this case, and likely others, state officials explained.

"This employee, within contractual work rules, performed vital services to help with the transition of ITS' 24-hour public safety help desk to a contracted 24/7 call center," the Office of Information Technology Services said in a statement.

The agency said its overtime will drop this year because it is no longer operating the help desk. It also bolstered its oversight of overtime.

"ITS has since enhanced administrative controls on overtime usage that include distributing updated overtime guidelines to all employees, as well as implementing continuous monitoring of overtime staffing requests and approvals to ensure that this type of scheduling anomaly will not be repeated."

Casais, who did not return calls seeking comment, was not alone in getting big overtime hours: 17 workers last year listed working more 2,000 hours of overtime, records from the state Comptroller's Office showed.

Last year, nine state workers exceeded that mark.

Others get big overtime

And over the past two years, Denise Williams, a security hospital training assistant at the Kirby Forensic Psychiatric Center, got more than 3,000 overtime hours each year, state records show.

But overall, overtime was down at state agencies in 2016, a 3 percent decline compared to 2015 -- a drop from $716 million to $694 million.

The workers with the highest number of overtime hours are usually at facilities that operate 24 hours a day, such as the prison and psychiatric centers.

But the overtime figures have drawn criticism as almost impossible, in some cases, raising questions about whether the state is adequately monitoring workers' time sheets.

Sen. Jeff Klein, D-Bronx, has conducted reports on overtime hours in recent years and has urged the state to more closely investigate the issue.

"I don’t think it’s too much to ask that state agencies should be aware, and they should have some kind of oversight where a red flag goes off when someone puts in for an inordinate amount of overtime," Klein said in 2015.

Questions raised

In 2014, The Journal News received through a Freedom of Information request the time cards of one of the then-perennial top overtime earners, a nurse at Bedford Hills Correctional Facility for Women in Westchester County.

Mercy Mathew's time cards showed she worked 90 percent of the available days between 2008 and 2013, the paper reported.

The Public Employees Federation, one of the state's largest public employees union, said the issue is a function of cutbacks in the state workforce, leading to fewer employees to do the work and thus more overtime.

Since Gov. Andrew Cuomo took office in 2011, the state workforce has declined by nearly 10,000 positions, state officials said. Cuomo has sought to limit state spending to less than 2 percent growth annually.

Overtime can either be deemed mandatory or volunteer by an agency, in accordance with collective-bargaining agreements.

"The bottom line for us is that agencies continue to be understaffed forcing the need for mandated or voluntary overtime," said Jane Briggs, a PEF spokeswoman.

State officials have countered they try to limit overtime while also controlling the size of the state workforce, which has about 119,000 workers in the executive branch.

About 94 percent of the state workforce is unionized.

"The alternative would be a larger, more bloated, more expensive and less efficient state bureaucracy that New York taxpayers simply can't afford," Morris Peters, a spokesman for the state Budget Division, said last month.

By the numbers

-- Overtime at state agencies in New York fell 3 percent last year compared to 2015, a drop from $716 million to $694 million, respectively.

-- Two state workers accrued more than 3,000 hours in overtime in 2016.

-- 17 workers last year listed working more 2,000 hours of overtime.

-- Some agencies require a lot of overtime because they operate 24 hours a day; some workers can use vacation time to offset time in the office.

-- The state Department of Corrections and Community Supervision had the most overtime last year: $205 million, up 3 percent from 2015.